v3.25.4

Related Party Transactions - Narrative (Details) |  | 8 Months Ended | 12 Months Ended
--- | --- | --- | ---
Apr. 30, 2024 | Dec. 31, 2024 USD ($) | Dec. 31, 2025 USD ($) $ / ft² | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($)
Related Party Transaction [Line Items] |  |  |  |  |
Related party transaction, amounts of transaction |  |  | $ 9,777,000 | $ 15,409,000 | $ 10,729,000
Development fees |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Related party transaction, amounts of transaction |  |  | 842,000 | 472,000 | 0
Leasing fees |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Related party transaction, amounts of transaction |  |  | 697,000 | 6,084,000 | $ 1,213,000
Vornado |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Management fee agreement value |  |  | 2,800,000 |  |
Other liabilities |  | $ 1,159,000 | $ 134,000 | 1,159,000 |
Vornado | Development fees |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Development fee as a percentage of development costs |  |  | 6.00% |  |
Other liabilities |  | $ 346,000 | $ 34,000 | 346,000 |
Vornado | Leasing fees |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Lease fee percentage of rent one to ten years |  |  | 3.00% |  |
Lease fee percentage of rent eleven to twenty years |  |  | 2.00% |  |
Lease fee percentage of rent twenty first to thirty years |  |  | 1.00% |  |
Percentage increase lease fee if broker used | 1.00% |  |  |  |
Percentage of third-party lease commission |  | 33.33% |  |  |
Percentage commissions on sale of assets under fifty million |  |  | 3.00% |  |
Asset sale commission threshold |  |  | $ 50,000,000 |  |
Percentage commissions on sale of assets over fifty million |  |  | 1.00% |  |
Other liabilities |  | $ 171,000 | $ 100,000 | 171,000 |
Vornado | Management, property management, cleaning, engineering and security fees |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Other liabilities |  | $ 642,000 |  | $ 642,000 |
Vornado | Retail space | Rego Park II | Property management, cleaning, engineering and security fees |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Property management fee, percent fee |  |  | 2.00% |  |
Vornado | Office and Retail Space | 731 Lexington Avenue | Property management, cleaning, engineering and security fees |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Property management fee agreement price per square foot | $ / ft² |  |  | 0.50 |  |
Vornado | Common Area | 731 Lexington Avenue | Property management, cleaning, engineering and security fees |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Property management fee escalation percentage per annum |  |  | 3.00% |  |
Vornado | Common Area | 731 Lexington Avenue | Base management fee |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Related party transaction, amounts of transaction |  |  | $ 387,000 |  |
Alexander's Inc. | Vornado | Vornado |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Parent ownership |  |  | 32.40% |  |
Alexander's Inc. | Director | Mr. Roth, Interstate, David Mandelbaum and Russell B, Wight, Jr. |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Ownership percentage by noncontrolling owners |  |  | 26.00% |  |
Alexander's Inc. | Director | Vornado | Mr. Roth, Interstate, David Mandelbaum and Russell B, Wight, Jr. |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Ownership percentage by noncontrolling owners |  |  | 2.30% |  |

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